Adding rule to check for old css variables and replace with v8 (#116)

* add rule

* fix for tests

* simple warning for template tags

* revert name

* fixes and more test cases

* added borderTop, borderBottom and stroke prop

* adding more cases and updating json

* added border replacement for fg = tests

* added CallExpression

* rm old test

* Update src/rules/new-color-css-vars.js

Co-authored-by: Josh Black <[email protected]>

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Co-authored-by: Katie Langerman <[email protected]>
Co-authored-by: Josh Black <[email protected]>